Nut tapping or screwing machine.



PATENTED MAY 22, 1906.

J. M. RALSTON.

NUT TAPPING OR SCREWING MACHINE.

APPLIUATION FILED JULY 25. 1905.

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wenn mmm no. mumanmms. mamma, n. n' i PATENTED MAY 22, 1906.

J. M. RALSTON. NUT TAPPING 0R SGREWING MACHINE.

APPLIOATION FILED JULY25. 1905.

4 SHEETS-SHEET 2.

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a- "l, f. .inn vmsswtnfx '4J-5ms@ 'l' Y No' 821376' PATENTED MAY 2z, 1906.

J- M. RALSTON.

NUT TAPPING 0R SCREWING MACHINE. APPLIGATION FILED JULYzs. 1905.

4 SHEETS-SHEET a PATENTED MAY 22, 1906. J. M. RALSTON.

NUT TAPPING OR SCREWING MAGHINE.

.LPPLIOATION FILED IULY. 1905.

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if@ fa 2o capable of receiving and holding uNrTEn STATES PATENT oE-EroE. JOHN MILLEE'EALSTQN, 0E BA'EEHEAD; SCOTLAND.

NUT TAPPING OR iSCREWINC- MACHINE.

ratente; May 22, 1906.

Application filed July 25, 1905. Serial No. 271,150.

have invented certain new and useful Im-V provements in Nut 'iapping-or Screwing Machines, of which the following is a specification.

This invention relates to machines for tapro ping or screwin nuts; and it has for its object to improve an simplify their construction. Under this invention the tap is held by means of grippers and is revolved in a vertical position, but without vertical movement, while the nuts are not revolved, but are fed automatically to the tap, one atv a time, from a vertical holder or magazine, in conjunction with which is a vertical forcer which works in guides and which is so made as lto be the nutblank in position and then descending, with theblank, and forcing it down and over the `screwed part of the tap, whereupon the forcer rises again m readiness to receive and tap an'- 2 5 other nut-blank.

, In order that my invention may be properly understood, I have hereunto appended explanatory drawings, whereon Figure 1 is a front view of the machine. Fig. 2 is a transverse Vvertical section of the machine, taken on the line :1c fr, Fig. 1. Fig. 3 is a back view of the machine. Fig. 4 is a plan of Fig. l. Fig. 5 is a horizontal section on the line y y, Fig. 2. Figs. 6, 7, and 8 are detail views. Fig. 9 is an enlarged sectional view of the grip mechanism. Fig. 1,0 shows a modification of the mechanism for operating the racks 7 and the slide 12. Fig. 11 is an enlarged view of the clutch-operating mechanism.

On the drawings the same reference characters wherever repeated indicate the same parts.

The machine consists of a rectangular box or frame a, supported on upri hts d and within which is a bearing-socket which carries the tapping mechanism c. This mechanism consists of a bevel gear-wheel e, which is driven from the bevel-wheelf on a main shaft carried inbrackets i, suitably secured to the outside of the box cby. means of the intermediate bevel-gearing h, mounted on a short shaft h,'which projects outside the box Yor frame c. l The'mam shaft is driven by the pulley from a'mtor, engine, or overhead shafting. The bevel-wheel e, which is supported by means of a cylindrical bush k, which rests uporrand revolves on ball-bearings 1 inside the cylindrical socket b, has fixed to its upper side a cylindrical frame m, which revolves along with the wheel e.-

Arranged to revolve along with the cylindrical frame m are two vertically-disposed. sliding plates g q, carrying a ring 'r at theirl upper ends, upon which a disk s rests and is held in place by a narrow ring t, fixed to the top of the sliding plates. Secured to the disk s are two links fuJ u, connected to rocking levers 'v lu, fulcrumed on the bar 29, carrie by the brackets- 29a. One of the levers 'v is connected by a link 28 to a cam-frame w', pivoted on bar 27a and which is actuated y a cam 'w on a secondary shaftl, which lat-- ter is carried in brackets 8 8,secured to the outside of the box or frame a, and is driven from the main shaft g by the pulleys 8*? and belt 8b. The vertically-reciprocating .disk s; has a central opening and works on a guide-- cylinder s', which is secured to the box a.) The bevel-wheel e, bush k, and socket b are; made with a central opening or passage-way, lrt, through which the nuts fall after being' tapped onto an inclined chute o, made in one;- with the bearing-socket b, and thereafter; they pass to a collectingbox or receiver p. Secured to the cylindrical frame m are two; sets of guides-a top set 2 and abottom set 2%1 (See also Fig.9.) The two pairs of grips?) 3% for holding the' tap in a vertical position'-J work (in opposite directions) inside each set@ 9o.; of guides. The grips 3 3a are opened andi closed upon the tap 4 by means of segments-S 5, carried on spindles 6, secured in the cylingj drical frame 'm and which engage with racks,.-

7 7 on the sliding plates g g. clearly at Fig. 9, the segments have toes 3b 3&3 which engage with notches in the grips. Tlgiejv upper grips 3 3 are moved inward, so as to grasp the tap 4 by means of the simultaneousaction of springs 6a 6b, (see Fig. 9,) while the, m9 grips 3a 3a are likewise caused to grip the tapby the action of' springs 4 4b. When thp; upper grips 3 3 engage the tap, they are held; positively in the engaged position by means of locking-bars g q', which are pivoted atg m5 q2. When the racks descend, the bars, whichpass through slots g3 in the rack-plates, arg,Y forced down by said plates out of engage-3 ment with the grips, while when the racks.- rise they are lifted up, so as to engage `thef I-:Lo

AS will be seevi; 95,-

' an 'extension 17 of the frame or boX c.

alternately moved out of engagement with.

the tap by the action of the toes 3b 3 of the segments, which engage with the notches and pull back the yrips (against the action of the springs) out o contact with the tap.

Formed in one with the guide-ring s is a narrow table 9, to which is bolted or otherwise secured a magazine or hopper for holding the nuts 11 to be tapped. Working in a slot at the bottom -of this magazine or hopper 1-0 is -a-sliding .plate 12, (see also plan view, -`IFig. 8,) whose inner end 13 is made somewhat V-shaped lto fit two adjacent sides of a nut, while to its outerend '14.isattached a frod 15, which passes through a hole :1'6 in The sliding plate 12 with rod 15 is reciprocated bythe -action o'f gthe spring 20, which 4thrusts it forward, and by a bell-crank lever 1.9, 4pivoted at 19a `-to the magazine 10, which pulls it back. When'necessary-sayjor instance,

whenstarting 'the -machine-the plate'can be pulled back by the handle 21.

Guided-bya hole 22-.in.an arm .23, secured to .themagazina is a hollow or tubular forcer 24,'which is expanded .a't lits lower end .and is made with a recess orjenlargement open at one side and which is of hexagon or other suitable shape at the interior, so Vas to snugly receive `and hold a nut, as shown at Fig. 8, when it is delivered to it 'by Athe slide 1.2. Thisforcer when a mut is being 'tap ed-eXerts a Ldownward pressure on the -nut by means of=a-spring 25, wound round the forcer 24'and Y latter is pivoted lto the lever 38, .the upper bearing against the arm 23 -and a .ring 26 on the forcer 24) and carries it down and over the screwed part .of the tap. The forcer 24 works insideioi` :and `is pinned to the fork of a lever v27, (seealso Eig. 6,) pivoted on the bar 27", (carried by the brackets 29a.) This lever 27 :is causedto lift up the forcer after each downward movement under the action of the spring 25 1by .means of lthe lever 38', acted on by the cam 34. As will be seen, 38 has -a screw 33, which bears against the under side of the lever 27. The forcer is guided .at its upper end, by the hole in the arm 22 and at its lower `end 'by beads 24a in thel uide-cylinder s', which engage with vertica grooves in theiorcer.

Pins 30.are fixed into the outer ends of .the rocking leversvo and bear'against the arms 31 of the double bell-crank lever 19, iulcrumed at 19a. This lever has a single central arm 18,which engages with a slot 32 (see Fig. 8) at the outer end of the sliding plate 12.

A cam projection 35 on the clutch part 36 actuates a toggle-joint 39 by means of the roller40, carried by the toggle-link 41, which end of which is forked, .so as to embrace the part 42 oi the clutch, while the lower end is ulcrumed at 43and is rprovided with acrankarm 47, having a weight The part 42 of the clutch is automatically 'put into engagement with the part 36 by the action of the weight 47 and is thrown out of engagement at the proper times by the action of the cam projection 35 on the to gle-joint 39.

The part 42 .can be held out o enga ement for a certain period by means of a roc er 44, pivoted at 44a, and which when held in the horizontal position under the action of a spring 46 engages a -detent 44b on 'the' lever 38a. The rocker can be thrown out of fengagement with the 'detent `by the raising of the rod 45, secured :to lthe vrocker and to .the lever 38. When the clutch is .fi-n gear, the cams 34 35 onthe-clutch part 36 andthe cam w on the sleeve extension 37 of the kclutch part are all put in action. 36 fand sleeve 37 are looseon the shaft Z.

The action of the machine is as follows: The magazine 10 is filled with Vnut-blanks and the machine started,'and thereafter the nutblanks are started to -feed by ulling :back the handle 21, sovas to allow the st blank to fall down onto the table 9. When'this is done, the spring 20 .acts -on the slide 12.-and-causes it to place the nut-blank on top of the tap 4 and in the =enlar ement at Athe lower Vend loi the forcer 24, .w ereupon the latter presses down the nut by the action ofthe spring 25 and forces it down and over the screwed part of the revolving =ta 4. The .forcer 24 iollows the nut dow-n t e:tap,and when :the nut is off .or clear of the screwedA art .at .the bottom of the tap the forcer is a lowed to drop, and-so, by means ofrod 45, which isattached to the Vlever 38, lcauses therocker 44 yto disengage the lever 38a, and so operates .the-.cams w34 35. During the time the-clutch 42 36 makes one revolution the cams fw 34 35 operate the levers fu 2-7 38, and-the -levers 'v force down the vdisk s and plates g with racks 7.

The clutch part IOO As the plates drop they re ease the pivoted bars g', whic opened laterally by the action of the segments 5. When the racks 7 drop, they cause the segments 5 to close the lower; ips 3a 3a and open the'tofp grips 3 3,thus1al owing the tapped nut to al from the top to the 'bottom grips, and at the same time the levers 'v move the bellcrank 19 and allow asecondl-nut to -fall onto the table 9. On vthe upward stroke oi levers 'u the motions are reversed, so as to close the upper grips and open the bottom rips, thereby allowing the tapped lnut to fall own the .passage n into the receiver p. During this same revolution the forcer 24 has been lifted by the action of cam 34 on levers allow the top grips 3 to be' IIO 38 and 27, and when the forcer is up clear of the tap another nut-blank .from the magazine is fed or placed onto the top of the tap and `held 'The clutch is kept out of gear until the forcer again descends and brings the clutch 42 again into action, as before. Lubricant for the tap is supplied tothe top of the tubular forcer andruns down same.

Durin the time that the cycle of operations as descri ed is being carried out the tap continues to revolve in the one direction, as there is always one of the pairs of grips holding the tap, the one pair belng onbefore the other is off. The bottom grips instead of being 'tightly held onto the tap by means of levers g are held in action by the springs 4a 4b, the tap being heldby the top grips when tapping or screwing the nut, the bottom grips only steadying'thetap to allow of the nut being cleared of the top grips.

A modification of the mechanism for operating the racks 7 and the slide 12 is shown at Fig. 10, In this case the cam-frame 'w' is provided with a downward extension w3 and is pivoted at 'L04 in the brackets 105, secured in the box' a. The extension has a pin we, which works in the slot fw7 of the lever w8, which is forked and is fulcrumed to the box a at w". Each prong of the fork is connected by a joint w10 to the disk ring t. IIt will be readily seen that as the cam w revolves it oscillates the extension 'w3 and lever w8, and so raises and lowers the disk s, plates q g, and racks 7 7. The cam 34 operates the lever 38, fulcrumed on the bracket lw5 at 29, which is in this case pin-jointed at 38h to the forcer 24. The slide 12 is operated by lever 19, which latter has a rod 19b jointed to it and also connected to the extreme end of the lever w8, so that the movements of said lever 'w8 are communicated to the slide 12, with the result that the latter is positively reciprocated.

Agrips out of the tap-holding position and comprising oscillatory members each for engaging a grip from one set on one excursion and a grip from the other set on the return excursion, segments carried by the respective oscillatory members, racks engaging the segments, and means for reciprocating vthe racks.

2. The combination of a frame, means for revolving the same, a plurality of sets of grips in the frame, racks and segments for operat- ,ing the grips for alternately grasping and holding a tap, means for forcing nut-blanks down and over the tap, a slide for automatically feeding the nut-blanks successively to the forcer, cams and levers for operating the forcer, the racks, and the slide, a driver for said cams, clutch mechanism for connecting the cams and driver, means controlled by the cams for throwing the clutch mechanism o'u't of gear, and means controlled by the forcer for throwing the clutch mechanism into gear.

3. The combination with a rotatable member, of two sets of tap-holding grips carried thereby, spring-pressed means for feeding blanks over the tap, cam mechanism, clutchcontrolled means for actuating the cam mechanism, means controlled by the cam mechanism for retracting the clutch after the release of the feeding means to the iniiuence of its spring, means controlled by the cam mechanism for retracting the feeding means and tensioning the spring thereof, and means controlled by the feeding means on the completion of its feeding movement for throwing the clutch into operative osition.

4. The combination wit a rotatable member, of two sets of tap-holding grips carried thereby, spring-pressed means for feeding blanks over the tap, cam mechanism, clutchcontrolled means for actuating the cam mechanism, means controlled by the cam mechanism for retracting the clutch after the release of the feeding means to the infiuence of its spring, means controlled by the cam mechanism for retracting the feeding means and tensioning the spring thereof, means controlled by the cam mechanism for presenting nut-blanks to the feeding means upon its retraction, and means controlled by the feeding means on the completion of its feeding movement for throwing the clutch into operative position.

5. In a nut-tapping machine, the combination with a rotatable member, of two sets of tapholding grips carried thereby, means for closing the grips, an oscillatory member having means for engaging the gri s of the respective sets and upon'its oscil ation in one direction retracting a grip of one set and upon its return retracting a grip of the other set, a sector carried by said oscillatory member, a reciprocatory rack in mesh therewith, and means for reciprocating said rack.

6. In a nut-tapping machine, the combination lwith a rotatable member, of two sets of tap-holding grips carried thereby, means for closing the grips, an oscillatory member having means for engaging the gri s of the respective sets and upon its oscil ation in one direction retracting a grip of one set and upon its return retracting a grip of the other set, a sector carried by said oscillatory member, a reciprocatory rack in mesh therewith, means for reciprocating said rack, means for locking one set of grips, and means carried by the racks for controlling said locking means.

7. In a nut-tapping machine, the combination with a rotary frame, of two sets of tapholding grips carried thereby, means for closing the grips, an oscillatory member having means for engaging the grips ofthe respective sets and upon its oscillation in one direc- IOO tion retractinga grip in one set and upon its return retracting the grip in the other set, a toothed sector carried by said oscillatory member, a slide mounted on said frame for reciprocation axially thereof, a rack carried by the slide and in mesh With said sector, a ring held from rotation and engaging the slides, cam mechanism for reciprocating said ring axially of the frame, means for locklng CHARLES C. NELSON. 

